It is important to note that Ignatius does not detail his sources for the story, and has no official confirmation from either the Israeli or American governments. The columnist is known as a non-partisan reporter with a strong track record and close links in US intelligence agencies, so his report is so far being taken seriously.

The alleged leaks are, to be clear, not highly sensitive secrets. Rather, they are technical details of the US offers to Iran in the nuclear talks, such as the number of centrifuges that Iran would be allowed to maintain. (The details of negotiations are always kept secret while they’re being hammered out, so that all parties can negotiate more freely, something Israeli negotiators have done themselves, for example in reaching the Oslo Accords.)

Ignatius’ sources contend that the Israeli leaks were not only secret but misleading, releasing incomplete information in a way that would make the US position on Iran appear more generous than it actually was. Those sources also point out that Israeli media began publishing these secrets in late January, just days after Obama and Netanyahu had a contentious Jan. 12 phone call over the Iran talks. Also in that window, Netanyahu announced he would visit the US to speak to Congress on a Republican invitation, undermining the White House.

The US reaction has allegedly been to reduce intelligence sharing with Israel. “US officials believed that Netanyahu’s office was the source of these reports and concluded that they couldn’t be as transparent as before with the Israel leader about the secret talks,” Ignatius reports.

This would be bad for everyone — including people who want a deal with Iran

It is worth reiterating that, even if Ignatius’ sources are correct, both the Israeli leaks and the US withholding are limited to the American negotiating terms with Iran, an important but relatively narrow topic within the wide field of US-Israel intelligence cooperation.

Still, the US and Israel have a long and productive track record of intelligence sharing, particularly when it comes to Iran, and this would be a worrying indication of the US-Israel breakdown. That should worry everyone, and not just observers who are skeptical of an Iran deal or who believe that preserving the level of US-Israel cooperation is more important.

Some proponents of a nuclear deal with Iran may welcome this news as demonstrating that Netanyahu is a bad actor who should be sidelined from the negotiations process. But this would be misguided, and even proponents of a deal should worry about this development. One reason that Iran is willing to negotiate at all is that the US has succeeded in putting enormous pressure on the country and its nuclear program — often with crucial Israeli help. That has meant both gathering intelligence and, in cases such as the 2010 cyberattack on centrifuges via the Stuxnet virus, offensive operations.

If the US and Israel cooperate less on Iran, and the pressure on Iran drops (or Tehran believes that it is likely to drop), then Iran has less incentive to make the painful concessions necessary to strike a deal, and a final nuclear deal is thus less likely to be achieved.

We are not necessarily at that point yet. But the possibility that the US might be limiting intelligence cooperating with Israel even on the narrow topic of Iran negotiations — and that Israel could potentially take actions that would predictably force the US to do so — is a worrying sign.